Duopoly Dynamics With A Barrier To Entry

This paper analyzes a dynamic mixed duopoly in which a profit-maximizing competitor interacts with a competitor that prices at zero (or marginal cost), with the cumulation of output affecting their relative positions over time. The modeling effort is motivated by interactions between Linux, an open-source operating system, and Microsoft's Windows in the computer server segment, and consequently emphasizes demand-side learning effects that generate dynamic scale economies (or network externalities). Analytical characterizations of the equilibrium under such conditions are offered, and some comparative static and welfare effects are examined.

A monopolist, knowing the demand curve for his product, can in a given period produce the quantity of this product which will maximize his profit. Any larger or smaller quantity will result in less profit. When another manufacturer starts producing the same or similar product, a duopoly results.

Fudenberg and Tirole use the game-theoretic issues of information, commitment and timing to provide a realistic approach to oligopoly.